The unplanned stops are also the result of a decision by United-Continental Holdings to replace long-range 777s with smaller, more cost-effective 757s on westbound routes from Europe to the US East Coast.

Single-aisle 757s require fewer crew and are cheaper to operate, but are not the usual aircraft of choice for transatlantic flights because of their shorter range: about 4,000 nautical miles.

757s can comfortably make transatlantic flights from airports such as London Heathrow or Amsterdam to the North East US coast – but only if the flight time is not extended because of wind, which uses up more fuel.

To safely avoid using up fuel reserves, United said its 757s were forced to stop 43 times to refuel out of nearly 1,100 US-bound flights, the Wall Street Journal reports.

The airline spokesperson said it has been compensating passengers in certain cases and added: “Headwinds returning from Europe are more extreme than we have seen in 10 years.”